[linux-2.6.36-git7: Power7] LTP Memory CGROUP Controller functional test creates Backtrace, OOMKill & rcu_sched_state detected stall jiffies

[Subrata Modak]

On Wed, 2010-10-27 at 09:45 +0900, KAMEZAWA Hiroyuki wrote: 
> On Tue, 26 Oct 2010 16:03:56 +0530
> Subrata Modak <subrata at linux.vnet.ibm.com> wrote:
> 
> > If you run LTP Memory CGROUP Controller functional test on
> > linux-2.6.36-git7, the following Backtrace, OOMKill & rcu_sched_state
> > detected stall jiffies are created. The machine is not reachable
> > thereafter. Ways to reproduce this problem:
> > 
> > 1) Build and boot kernel 2.6.36-git7 on Power7 machine with attached
> > config file,
> > 2) Fetch, build and install LTP:
> > 	git clone git://ltp.git.sourceforge.net/gitroot/ltp/ltp
> > 	cd ltp
> > 	./configure
> > 	make
> > 	make install
> > 3) Create a LTP runtest file /opt/ltp/runtest/memcg_function_test with
> > the following entry:
> > memcg_function          memcg_function_test.sh
> > <<EOF>>
> > 	cd /opt/ltp
> > 	./runltp -f memcg_function_test
> > 
> 
> IIUC, memcg test includes intentional OOM-Kill test by setting the limit to 0.
> And it has another test to set the limit to PAGE_SIZE.
> 
> In your environemnt, I think page size is 64kb...right ?
> 
> About rcu_sched_state()....I have no idea at this stage. I reviewed memcontrol.c
> and oom_kill.c again and coundn't found anything in quick review.
> 
> Could you try again after -rc1 shipped ?

Oh Sure, I saw this mail now. I will try it out on the latest git tree
available :-)

Regards--
Subrata

> I think Andrew Morton sent some amount of updates for oom_kill and memcg, vmscan
> to Linus, today.
> 
> Thanks,
> -Kame
>